Cross-Networks Energy Efficiency Tradeoff: From Wired Networks to Wireless Networks

The tremendously large number of increasing Internet protocol (IP) packets call for quality of service (QoS) guaranteed packets transmission with low-delay, high throughput, and high energy efficiency (defined as the transmitted bits per unit energy consumption) in the fifth-generation (5G) networks. For this motivation, wavelength division multiplexing (WDM) networks and the next generation of wireless technologies are two major methods in the wired and wireless networks, respectively. However, the existing energy efficient switch fabric and wireless technologies have focused on either wired or wireless networks, only separately. The joint cross-networks optimization for energy efficiency in 5G remains unexplored. This does not fully facilitate the QoS guaranteed packets transmission and energy efficient networks planning from the viewpoint of cross networks. In this paper, we formulate a joint optimization model to enhance the performance of energy efficiency in 5G. In particular, each base station is equipped with a set of parallel tunable lasers for simultaneous transmission of multiple packets from the uplink users in the cell as well as the data center networks. We propose a novel joint cross-networks scheduling and routing (JCNSR) algorithm according to the wireless channel quality of users, user data rate, and the topology constraint. The IP packets are then delivered to the targeted cells via a transport layer in the WDM network and further transmitted to the targeted users via wireless channels under the constraint of delay. Based on the idea of the cross-networks tradeoff between the delay and the energy efficiency, JCNSR can achieve high-energy efficient transmission with performance guarantee. The effectiveness of the proposed framework is verified by extensive simulations.